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diff --git a/xorg-server/hw/xfree86/modes/xf86cvt.c b/xorg-server/hw/xfree86/modes/xf86cvt.c
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+/*
+ * Copyright 2005-2006 Luc Verhaegen.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+/*
+ * The reason for having this function in a file of its own is
+ * so that ../utils/cvt/cvt can link to it, and that xf86CVTMode
+ * code is shared directly.
+ */
+
+#ifdef HAVE_XORG_CONFIG_H
+#include <xorg-config.h>
+#else
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+#endif
+
+#include "xf86.h"
+#include "xf86Modes.h"
+
+#include <string.h>
+
+/*
+ * Generate a CVT standard mode from HDisplay, VDisplay and VRefresh.
+ *
+ * These calculations are stolen from the CVT calculation spreadsheet written
+ * by Graham Loveridge. He seems to be claiming no copyright and there seems to
+ * be no license attached to this. He apparently just wants to see his name
+ * mentioned.
+ *
+ * This file can be found at http://www.vesa.org/Public/CVT/CVTd6r1.xls
+ *
+ * Comments and structure corresponds to the comments and structure of the xls.
+ * This should ease importing of future changes to the standard (not very
+ * likely though).
+ *
+ * About margins; i'm sure that they are to be the bit between HDisplay and
+ * HBlankStart, HBlankEnd and HTotal, VDisplay and VBlankStart, VBlankEnd and
+ * VTotal, where the overscan colour is shown. FB seems to call _all_ blanking
+ * outside sync "margin" for some reason. Since we prefer seeing proper
+ * blanking instead of the overscan colour, and since the Crtc* values will
+ * probably get altered after us, we will disable margins altogether. With
+ * these calculations, Margins will plainly expand H/VDisplay, and we don't
+ * want that. -- libv
+ *
+ */
+_X_EXPORT DisplayModePtr
+xf86CVTMode(int HDisplay, int VDisplay, float VRefresh, Bool Reduced,
+ Bool Interlaced)
+{
+ DisplayModeRec *Mode = xnfcalloc(1, sizeof(DisplayModeRec));
+
+ /* 1) top/bottom margin size (% of height) - default: 1.8 */
+#define CVT_MARGIN_PERCENTAGE 1.8
+
+ /* 2) character cell horizontal granularity (pixels) - default 8 */
+#define CVT_H_GRANULARITY 8
+
+ /* 4) Minimum vertical porch (lines) - default 3 */
+#define CVT_MIN_V_PORCH 3
+
+ /* 4) Minimum number of vertical back porch lines - default 6 */
+#define CVT_MIN_V_BPORCH 6
+
+ /* Pixel Clock step (kHz) */
+#define CVT_CLOCK_STEP 250
+
+ Bool Margins = FALSE;
+ float VFieldRate, HPeriod;
+ int HDisplayRnd, HMargin;
+ int VDisplayRnd, VMargin, VSync;
+ float Interlace; /* Please rename this */
+
+ /* CVT default is 60.0Hz */
+ if (!VRefresh)
+ VRefresh = 60.0;
+
+ /* 1. Required field rate */
+ if (Interlaced)
+ VFieldRate = VRefresh * 2;
+ else
+ VFieldRate = VRefresh;
+
+ /* 2. Horizontal pixels */
+ HDisplayRnd = HDisplay - (HDisplay % CVT_H_GRANULARITY);
+
+ /* 3. Determine left and right borders */
+ if (Margins) {
+ /* right margin is actually exactly the same as left */
+ HMargin = (((float) HDisplayRnd) * CVT_MARGIN_PERCENTAGE / 100.0);
+ HMargin -= HMargin % CVT_H_GRANULARITY;
+ } else
+ HMargin = 0;
+
+ /* 4. Find total active pixels */
+ Mode->HDisplay = HDisplayRnd + 2*HMargin;
+
+ /* 5. Find number of lines per field */
+ if (Interlaced)
+ VDisplayRnd = VDisplay / 2;
+ else
+ VDisplayRnd = VDisplay;
+
+ /* 6. Find top and bottom margins */
+ /* nope. */
+ if (Margins)
+ /* top and bottom margins are equal again. */
+ VMargin = (((float) VDisplayRnd) * CVT_MARGIN_PERCENTAGE / 100.0);
+ else
+ VMargin = 0;
+
+ Mode->VDisplay = VDisplay + 2*VMargin;
+
+ /* 7. Interlace */
+ if (Interlaced)
+ Interlace = 0.5;
+ else
+ Interlace = 0.0;
+
+ /* Determine VSync Width from aspect ratio */
+ if (!(VDisplay % 3) && ((VDisplay * 4 / 3) == HDisplay))
+ VSync = 4;
+ else if (!(VDisplay % 9) && ((VDisplay * 16 / 9) == HDisplay))
+ VSync = 5;
+ else if (!(VDisplay % 10) && ((VDisplay * 16 / 10) == HDisplay))
+ VSync = 6;
+ else if (!(VDisplay % 4) && ((VDisplay * 5 / 4) == HDisplay))
+ VSync = 7;
+ else if (!(VDisplay % 9) && ((VDisplay * 15 / 9) == HDisplay))
+ VSync = 7;
+ else /* Custom */
+ VSync = 10;
+
+ if (!Reduced) { /* simplified GTF calculation */
+
+ /* 4) Minimum time of vertical sync + back porch interval (µs)
+ * default 550.0 */
+#define CVT_MIN_VSYNC_BP 550.0
+
+ /* 3) Nominal HSync width (% of line period) - default 8 */
+#define CVT_HSYNC_PERCENTAGE 8
+
+ float HBlankPercentage;
+ int VSyncAndBackPorch, VBackPorch;
+ int HBlank;
+
+ /* 8. Estimated Horizontal period */
+ HPeriod = ((float) (1000000.0 / VFieldRate - CVT_MIN_VSYNC_BP)) /
+ (VDisplayRnd + 2 * VMargin + CVT_MIN_V_PORCH + Interlace);
+
+ /* 9. Find number of lines in sync + backporch */
+ if (((int)(CVT_MIN_VSYNC_BP / HPeriod) + 1) < (VSync + CVT_MIN_V_PORCH))
+ VSyncAndBackPorch = VSync + CVT_MIN_V_PORCH;
+ else
+ VSyncAndBackPorch = (int)(CVT_MIN_VSYNC_BP / HPeriod) + 1;
+
+ /* 10. Find number of lines in back porch */
+ VBackPorch = VSyncAndBackPorch - VSync;
+
+ /* 11. Find total number of lines in vertical field */
+ Mode->VTotal = VDisplayRnd + 2 * VMargin + VSyncAndBackPorch + Interlace
+ + CVT_MIN_V_PORCH;
+
+ /* 5) Definition of Horizontal blanking time limitation */
+ /* Gradient (%/kHz) - default 600 */
+#define CVT_M_FACTOR 600
+
+ /* Offset (%) - default 40 */
+#define CVT_C_FACTOR 40
+
+ /* Blanking time scaling factor - default 128 */
+#define CVT_K_FACTOR 128
+
+ /* Scaling factor weighting - default 20 */
+#define CVT_J_FACTOR 20
+
+#define CVT_M_PRIME CVT_M_FACTOR * CVT_K_FACTOR / 256
+#define CVT_C_PRIME (CVT_C_FACTOR - CVT_J_FACTOR) * CVT_K_FACTOR / 256 + \
+ CVT_J_FACTOR
+
+ /* 12. Find ideal blanking duty cycle from formula */
+ HBlankPercentage = CVT_C_PRIME - CVT_M_PRIME * HPeriod/1000.0;
+
+ /* 13. Blanking time */
+ if (HBlankPercentage < 20)
+ HBlankPercentage = 20;
+
+ HBlank = Mode->HDisplay * HBlankPercentage/(100.0 - HBlankPercentage);
+ HBlank -= HBlank % (2*CVT_H_GRANULARITY);
+
+ /* 14. Find total number of pixels in a line. */
+ Mode->HTotal = Mode->HDisplay + HBlank;
+
+ /* Fill in HSync values */
+ Mode->HSyncEnd = Mode->HDisplay + HBlank / 2;
+
+ Mode->HSyncStart = Mode->HSyncEnd -
+ (Mode->HTotal * CVT_HSYNC_PERCENTAGE) / 100;
+ Mode->HSyncStart += CVT_H_GRANULARITY -
+ Mode->HSyncStart % CVT_H_GRANULARITY;
+
+ /* Fill in VSync values */
+ Mode->VSyncStart = Mode->VDisplay + CVT_MIN_V_PORCH;
+ Mode->VSyncEnd = Mode->VSyncStart + VSync;
+
+ } else { /* Reduced blanking */
+ /* Minimum vertical blanking interval time (µs) - default 460 */
+#define CVT_RB_MIN_VBLANK 460.0
+
+ /* Fixed number of clocks for horizontal sync */
+#define CVT_RB_H_SYNC 32.0
+
+ /* Fixed number of clocks for horizontal blanking */
+#define CVT_RB_H_BLANK 160.0
+
+ /* Fixed number of lines for vertical front porch - default 3 */
+#define CVT_RB_VFPORCH 3
+
+ int VBILines;
+
+ /* 8. Estimate Horizontal period. */
+ HPeriod = ((float) (1000000.0 / VFieldRate - CVT_RB_MIN_VBLANK)) /
+ (VDisplayRnd + 2*VMargin);
+
+ /* 9. Find number of lines in vertical blanking */
+ VBILines = ((float) CVT_RB_MIN_VBLANK) / HPeriod + 1;
+
+ /* 10. Check if vertical blanking is sufficient */
+ if (VBILines < (CVT_RB_VFPORCH + VSync + CVT_MIN_V_BPORCH))
+ VBILines = CVT_RB_VFPORCH + VSync + CVT_MIN_V_BPORCH;
+
+ /* 11. Find total number of lines in vertical field */
+ Mode->VTotal = VDisplayRnd + 2 * VMargin + Interlace + VBILines;
+
+ /* 12. Find total number of pixels in a line */
+ Mode->HTotal = Mode->HDisplay + CVT_RB_H_BLANK;
+
+ /* Fill in HSync values */
+ Mode->HSyncEnd = Mode->HDisplay + CVT_RB_H_BLANK / 2;
+ Mode->HSyncStart = Mode->HSyncEnd - CVT_RB_H_SYNC;
+
+ /* Fill in VSync values */
+ Mode->VSyncStart = Mode->VDisplay + CVT_RB_VFPORCH;
+ Mode->VSyncEnd = Mode->VSyncStart + VSync;
+ }
+
+ /* 15/13. Find pixel clock frequency (kHz for xf86) */
+ Mode->Clock = Mode->HTotal * 1000.0 / HPeriod;
+ Mode->Clock -= Mode->Clock % CVT_CLOCK_STEP;
+
+ /* 16/14. Find actual Horizontal Frequency (kHz) */
+ Mode->HSync = ((float) Mode->Clock) / ((float) Mode->HTotal);
+
+ /* 17/15. Find actual Field rate */
+ Mode->VRefresh = (1000.0 * ((float) Mode->Clock)) /
+ ((float) (Mode->HTotal * Mode->VTotal));
+
+ /* 18/16. Find actual vertical frame frequency */
+ /* ignore - just set the mode flag for interlaced */
+ if (Interlaced)
+ Mode->VTotal *= 2;
+
+ {
+ char Name[256];
+ Name[0] = 0;
+
+ snprintf(Name, 256, "%dx%d", HDisplay, VDisplay);
+
+ Mode->name = xnfalloc(strlen(Name) + 1);
+ memcpy(Mode->name, Name, strlen(Name) + 1);
+ }
+
+ if (Reduced)
+ Mode->Flags |= V_PHSYNC | V_NVSYNC;
+ else
+ Mode->Flags |= V_NHSYNC | V_PVSYNC;
+
+ if (Interlaced)
+ Mode->Flags |= V_INTERLACE;
+
+ return Mode;
+}